overte/interface/resources/shaders/metavoxel_heightfield_cursor.vert
2014-10-14 15:21:45 -07:00

29 lines
954 B
GLSL

#version 120
//
// metavoxel_heighfield_cursor.vert
// vertex shader
//
// Created by Andrzej Kapolka on 8/7/14.
// Copyright 2014 High Fidelity, Inc.
//
// Distributed under the Apache License, Version 2.0.
// See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//
// the height texture
uniform sampler2D heightMap;
void main(void) {
// compute the view space coordinates
float height = texture2D(heightMap, gl_MultiTexCoord0.st).r;
vec4 viewPosition = gl_ModelViewMatrix * (gl_Vertex + vec4(0.0, height, 0.0, 0.0));
gl_Position = gl_ProjectionMatrix * viewPosition;
// generate the texture coordinates from the view position
gl_TexCoord[0] = vec4(dot(viewPosition, gl_EyePlaneS[4]), dot(viewPosition, gl_EyePlaneT[4]),
dot(viewPosition, gl_EyePlaneR[4]), 1.0);
// the zero height should be invisible
gl_FrontColor = vec4(1.0, 1.0, 1.0, 1.0 - step(height, 0.0));
}